[307malibu]

Allright, I was all excited to have the new motor fired tonight and now I'm screwed. Or so it seems. Here's the background:

I rented an oil pump primer from the local parts store. It wouldn't engage and, on closer inspection, I noticed that the "key" that engages the oil pump shaft seemed to be way big. I compared the primer to my oil points distributor and saw that the points distributor key was much smaller. I cursed the Taiwanese engineer who designed the oil pump primer I rented, then had a buddy lathe off the cam teeth on my old points distributor (I was running a Mallory HEI on the old 307), then primed 'er up. My life was good.

I set the valves and did some other stuff. When about to drop in my HEI, I couldn't get it to seat. No biggie, right? Wrong. No matter what, I couldn't get the HEI to engage the oil pump shaft. Then I turned it over. Crap. It's got the much bigger "key," just like that tiawanese-made primer!

Looks like the problem is my oil pump shaft, not the distributor! So. . . . other than pulling the motor and replacing the oil pump shaft (I don't know why this is an issue, by the way, since I just got a standard chevy hardened shaft) what are my options?

I noticed they make .500 and .491 distributor gears. Can I just swap out the gear? Can I find an old points distributor (one without the cam teeth ground off) and swap out the gear from that?

Sorry about length, but I figured the whole story might be helpful. Thanks in advance!!!

[307malibu]

By the way, this is a '97 Silverado 350 with the factory roller cam setup. Any thoughts?

Thanks!

[BBCMudbogger]

Points and HEI do not belong in the same sentence let alone the same distributor. I am guessing it is a stock computer controlled truck? If it is then neither a points type or an HEI will work in your 97

[307malibu]

I converted it to a carb . . . it's in a '71 Chevelle. (Sorry I left that out to begin with!)

[307malibu]

Here's an update .. . I remembered I had an old junkyard HEI (1970s-era) in my Dad's attic, so I got that and test-fit it. Drops all the way in, just like it's supposed to. Yay. Seems like the Mallory HEI's oil pump "key" is just a little too big for the oil pump shaft I've got. Go figure, since it fit the old 307 just fine. I measured the Mallory's "key" at .210 and the 1970s one at .190. Guess that's all I needed. Now I'm just going to swap the gear from the old HEI to the new one. I've heard this can be tricky--a buddy (who is going to give me a hand later, said he's cracked a lot of these cast gears in the process; he is a 2.3 ford turbo guy, so I'm not sure if those are different)--you guys got any tips on this? Thanks!

[74Ventura]

Hi there..The key is part of the shaft not a part of the gear.You could possibly remove the gear and carefully file/grind the key thinner,hopefully evenly on each side.I have no idea if that will work for you,maybe some of the more experienced members can chime in on this?

[Jmark]

Originally Posted by 74Ventura

Hi there..The key is part of the shaft not a part of the gear.You could possibly remove the gear and carefully file/grind the key thinner,hopefully evenly on each side.I have no idea if that will work for you,maybe some of the more experienced members can chime in on this?

Yep, a truthful statement! Grinding "may" work but would not be high on my list of "fixes" unless you can remove equal amounts from each side so as not to make it spin out of round.

[307malibu]

Thanks for the help, guys. I ended up grinding just a little bevel into the sides of the "key" on end of the distributor shaft and that got it to seat. There was no bevel on the Mallory shaft, but there was on the junkyard HEI I had and the old point distributor. It seats all the way now, so I'm happy with that! Thanks again!!!